1. Field
One or more embodiments described herein relate to a wafer cutting apparatus.
2. Description of the Related Art
Various cutting processes have been developed to divide wafers into semiconductor chips. One process uses a diamond blade to saw wafers. This process generates wafer particles that may adversely affect chip performance. Cleaning the wafer is also an issue. Also, truncating water is required to be injected during blade sawing in order to reduce temperature. All of these increase costs and processing time.
Another process uses a laser to cut wafers. During this process (known as stealth cutting), the position of a focal point of the laser is aligned with the middle of the wafer. This process has several drawbacks. For example, punching height is a concern. Also, some chips may not be completely divided when cut from the top. When cut from the bottom, thermal damage may result that impairs proper operation of the divided chips.